Automatic reset circuit breaker



July 16, 1935. w. H. FRANK I AUTOMATIC RESET CIRCUIT BREAKER Filed April21, 1933 3 Sheets-Sheet l INVENTOR.

LINE

ATTORNEY.

July 16, 1935. w, H FRANK 2,008,174

AUTOMATIC RESET CIRCUIT BREAKER Filed April 21, 1933 3 Sheets-Sheet 2Zea L INVENTOR.

BY ,J {QM ATTORNEY.

July 16, 1935. V w. H. FRANK 2,008,174

AUTOMATIC RESET CIRCUIT BREAKER Filed April 21, 1933 5 Sheets-Sheet 5INVENTOR.

MM .4/i/

L %QQW ATTORNEY.

Patented July 16, 1935 UNITED STATES PATENT. OFFICE.

AUTOMATIC RESET CIRCUIT BREAKER Application April 21, 1933, Serial No.sense 14 (Claims. (Cl. ire-2st) This invention relates to automaticallyresetting circuit protective devices and can best be understood withreference to a copendlng application, Serial No. 667,149, filed April21, 1933.

5 In the prior application above mentioned, there is disclosed anautomatically resetting circuit breaker. The instant applicationdiscloses an automatically resetting circuit breaker, whichfundamentally is like the circuit breaker disclosed in the abovementioned application, but which further includes an automaticallyoperated ofi holding means, for holding the circuit breaker in opencircuit so that when the contact arrn moves to open circuit position onoverload, it will automatically be held in such open circuit position,until the overload is taken off or cut out of the line.

It will be observed that it is not considered desirable to have thecircuit breaker held open after the overload has been taken off or outout of the line, because so to hold it open, would require the user toreset it manually.

The invention, therefore, aims to provide in connection with anautomatically resetting circuit breaker, an automatically operatingmeans for holding the circuit breaker in open position, the means beingconstructed torelease and close the breaker when the overload is takenoff or cut out of the line.

In view of the fact that the means which takes the overload off theline, or cuts it out of the line, may be remote from the breaker, it canbe said that the invention provides a remotely controlled automaticallyresetting circuit breaker 35 having an automatically operating means forholding the circut breaker in open position, the

means being constructed to release and close when a remotely positionedmeans is operated to take off or cut out of the line, the overload 40condition. 1

Other objects of the invention will presently appear upon reference tothe following detailed description of a preferred embodiment of thesame, the embodiment being shown in the appended drawings. In thesedrawings,

Fig. 1 is a structural diagrammatic view of the embodiment.

Fig. 2 shows the embodiment in top plan view.

Figs. 3 and e are, respectively, elevation and end sections of the same.

Fig. 5 is a section on line 5-5 of Fig. 2.

Figs. 6, 7 and 8 are views like those of Figs. 2, 3 and 4, but showingthe parts in overload release" position.

Fig. 9 is a section on line 89 of Fig. 6.

Figs. 10 and ii are detailed views, in plan and elevation, of a criticaipart of the embodiment.

Figs. 12, i3 and i i, are respectively, plan, elevation, and end sectionviews of the embodiment in an ofi position created by movement of a 5manual control handle.

The breaker of Figs. 1-10 The automatically resetting circuit breaker ofthis application, like the breaker of Figs. 1-10 of the priorapplication mentioned, is characterized by the fact that the thermalelement moves in the direction of the operating shaft, and functions torelease the breaker shaft for trip or reset. The breaker parts aremounted upon a base it of insulating material and are enclosed within acover, also or insulating material, the cover having slots through whicrejects the two manually engageable parts of breaker, namely, thewinding drum i2 and the manual control handle i l. The e parts will nowbe described specifically -ivotaliy mounted axle pin it, to and betweenlured frame plates ll, is the breaker contact "o. l8, the arm having acontact 09 for the fixed line contact 263 of the Pivotally connected. byan aide pin ll, to two upstanding parts or the breaker contact arm USare connecting rod links 22 which at their upper ends are connected to acrank 3-0 formed on breaker operatin it, the lat- "er being trunnionedin aligned bea rig holes of the upstanding irame plates it is observedthat the rotation of the operating shaft 24 0perates, through the mediumor the crank 23 and the connecting rod links 2 to move the contact armto and from contact making and breaking position, and that the crank andlinks provide a toggle clamping action for the arm, when the latter isin 021" position.

One end of the operating shaft is bent perpendicularly from the axis ofthe shaft to provide a holding crank iii, adapted to be held by one oranother of the stops, provided on the thermal element, refer ncedgenerally T. ihe latter is connected by a flexible lead 250. at one end,to arm l8 and at the other to the load. I

The "on holding stop, is to say, the stop which holds the holding crank25 in the on position, is referenced and is in the nature of a lugprovided on a plate ill which bridges the upper ends of the relativelyelectrically and mechemically connected, upstanding, thermal bimetallicwarping strips 28 of the element T 5 which holds the crank 25 in the oposition,-

and is insulated from these ends by an insulat strip 29. The other stop,that is to say, the stop Figs. 6 to 8, is referenced 3d, and is also inthe nature of a lug provided on the plate 2?. The stop till has a notch3i directly in line with the stop 26, and has a tooth 38a somewhat outof line from stop 26.

The lower ends of the strips 28 of bimetallic material, forming thethermal element, are mounted on a bracket 32 in turn positioned upon ablock of insulating material 33, disposed in a depression in the uppersurface of the and mounted on key and groove runways therein, and soproportioned as to be able to slide in such depression in a directionparallel to the axis of the operating shaft 241.

For manually sliding the block 33 in its depression, there is providedan actuating device whose handle has previously been referred to a amanual control handle it. This handle is journalled inthe'base M on theend of a cross shaft 34, which shaft is provided with an upstandingfinger engaging in a notch in the lower surface of block 33, and it willbe observed that movement of the actuating handle iilrotates the shaft8G and slides the block 33 in its depression. For latching the handle itin the on position of Fig. 4 or in the ofi position of Fig. it, there isprovided a spring 3'? adapted to engage one or another of a pair ofnotches 38, formed in that part of the handle near the shaft 8%.

0n the end of the operating shaft opposite that end thereof which isformed as a holding crank 25, is a drum previously .referenced l2 andcontaining a clock spring (not shown) wound upon the end of theoperating shaft and having one end fixed to the shaft and the other endfixed to the drum. This spring tends to rotate the operating shaftclock-wise and its influence is opposed by the stops 26 and 3mpreviouslymentioned.

For winding the spring, the user rotates the drum, which is rotatablyjoumalled on the shaft,

, and is held against reverse rotation by a ratchet wheel I3 fixed tothe drum and disposed between a frame plate l1 and the drum, asindicated in Fig. 2. A clockwork pawl cooperates with the ratchet toprevent movement of the drum in the counter-clockwise direction as thedrum is being rotated to wind the spring, it being observed that thedrum can be wound by moving itwith the thumb, ascan readily be seen fromFig. 3. I

11' desired, the shaft 24 may be operatively connected, as by gears, toa conventional speed reducduce the'speed of operation of the device.

provided a means which specifically embraces much or the novelty thatthis application possesses over the copending application Serialilo.667,149, flied April 21, 1933, above mentioned. In order toaid in theunderstanding of this device, reference will be had particularly to Fig.1

As indicated in this figure, there is electrically connected in parallelwith the contact arm l8 and the thermal element '1', an electro-magnet41 whose energizingicircuit (shunting the main cir-.

cult) is adapted to be closed. by a pair 01 contacts 4|, which engage toclose the magnet circuit when aooarvs the contact arm l 8 is elevated onoverload. When this electro-magnet is energized, that is to say, afterthe breaker has opened, it rotates bell crank 69 about the fixed pivotbe against the influence of spring 56 and projects a stop lug 52 of thebell crank under the notch 88 of the ad stop, this lug in this positionsolong as the magnet remains energized. With the lug 52 under notch 3i,return of the thermal element, due to cooling after overload, does notcause return of the crank 25 tq on position, the crank being engaged bythe lug 52 and being held in off position.

The magnet remains energized until the over-- load is taken off or cutout of the line, that is to say, when the service switch 53is opened.When this is done, the magnet is de-energized, releasing the bell crank49 and the holding crank 25. The shaft 24 then rotates to on position,resetting the circuit breaker for normal use.

The parts just described in connection with the diagrammatic disclosureof Fig. 1 will now be described more completely in connection with theother figures of the drawings which show the parts structurally and morein detail. The electromagnet il is fixedly mounted on the frameconsiderably above the base of the breaker and is electrically connectedto the line conductor which goes to the contact it. Through the contacts18,

the other side of the magnet is electrically con- Y nected to the load.The lower one of the contacts 38 has an extension 63 of insulatingmaterial spring having one end adjustably anchored to the frame. Thestop lug 52 of the bell crank as is bent laterally from the bell crankso that it can be placed in alignment with and under the notch 88, inthe path 0? the crank 25.

The operations of the breaker will now be described in complete detail.

Assume the parts to be in on position. At

this time the holding crank 25 engages andis disposed under the on stop26 and the operating shaft and. its associated parts are held in the"on" position, with the contact arm I8 in a horizontal position, so thatcontact I9 engages contact 20, the parts being held against theinfiuence of the spring which tends to rotatethe operating shaftclockwise. It is observed that the thermal element T. occupies such aposition on normal load that the stop 28 is directly in line withholding crank 25. Y

Upon the arising of an overload, the thermal element T" will warp in thedirection of the axis of the operating shaft 24, that is to say, towards'the right of Fig. 4, sumciently to move stop 26 away from the holdingcrank 25. The springin drum l2 consequently rotates the parts clockwisewith an extremely rapid movement. Such rota.- tion causes an upward pullon the connecting rod links 22 and pivots contact arm l8 to thepositionot Hg. '1 from the position of Fig. 3; that is to any. opens thecircuit. When thermal element T" is warped to the right of Fig. 4, itplaced tooth 3 la in line with the crank 25. Consequently the crankrotates on overload but one-half turn and is engaged by the top of stop30, to restrain further rotation of the parts. When the circuit has beenopened sufiiciently long for the thermal element T to cool and warp backto its original position, the stop 30 will move away from crank 25 andnotch 3i will be placed in line with this crank.

'This does not, however, free the operating shaft to rotate back to onposition, because of the intervention of the automatically operatedlatch previously described, it being observed that when the contact arml8 moved, to open circuit position on overload, it caused magnet 41 tobe energized and caused stop lug 52 to be placed under notch iii, in thepath of crank '25, to hold the crank in off position.

The parts remain in this position until the defective load consunnngdevice is taken oil the line, or until the switch 53 is opened. Eitherof these operations deenergizes magnet 41 and frees the operating shaft,for rotation. With the operating shaft free to rotate, the spring willrotate the shaft another half turn clockwise to reset the breaker and tobring holding crank 25 once more under and against stop 26.

For manual control operation, the actuating handle it is utilized. Ifthe breaker is to be moved from the on position, Fig. 3, to the offposition, Fig. 13, the handle I4 is moved from the position of Fig. 4 tothe position of Fig. 14. Such movement of the handle causes the block 33to slide to the right and this movement, carrying the thermal element"1" with the block, takes the stop 26 out of the path of the crank 25and places the tooth 3m in the path of the crank 25. The spring in drumI 2 then rotates the operating shaft to off position.

i To restore the parts to on position, the actuating handle is movedback to the position of Fig. 3 which serves to place notch 3! in linewith crank 25, freeing the latter and the shaft for movement by thespring in drum i2 which then rotates the shaft until the crank 25 isengaged by the stop 26.

Auxiliaries It is at present contemplated to combine with the devicesshown in this application, and the combinations efiected through the useof these devices, certain auxiliaries which are not 'here disclosed butwhich are disclosed in detail in certain copending applications whichare being filed simultaneously herewith.

For example, in application Serial No. 667,149, filed April 21, 1933,there are disclosed in Figs. 1-10 and 11-18 two different forms ofcircuit breakers, and it is at present contemplated to combine the novelmeans of this application with either of those forms of breakers.Similarly, it is contemplated to combine the novel means of thisapplication with the multipole unit of Figs. 19-28 of that application,and with the controlling breaker relays of Figs, 20-30 of thatapplication.

Further, in application Serial No. 667,151, filed April 21, 1933, thereis shown a wind demand latch and indicator, and a spring rewindingdevice, either or both of which devices may be inoorporated in thecircuit breaker here shown to function in a manner described in theapplication just mentioned.

Further, in application Serial No. 667,152, filed April 21, 1933, thereis shown a means for limiting the number of cycles of overload releaseand automatic reset that can occur before the operator is called upon toreset the device. This auxiliary may be added to the breaker here shown,if desired, with the instant device being constructed to operate on anydesired one of the limited number of cycles permitted by the device ofsaid application.

Further, various combinations of the devices and features here shown andof the devices and features shown in the copending applications justreferred to may be eifected, and it is the present intention to cover inthis application, as well as in the applications above referred tocombinations of the auxiliaries specifically shown in those applicationswith any or all of the devices or combinations here shown.

I claim:

1. An automatic release and reset circuit protecting breaker includingautomatically operating releasing and resetting mechanism, meansoperable for opening the breaker controlled line, and means operableautomatically after, and supplied with electrical energy only by andupon, an automatic release operation of said mechanism for preventingautomatic reset operation of said mechanism until the breaker-controlledline is opened by operation of the first mentioned means.

2. An automatic release and reset circuit protecting breaker includingautomatically operating releasing and resetting mechanism, meansoperable for opening the breaker controlled line, and means operableautomatically after, and supplied with electrical energy only by andupon, an automatic release operation of said mechanism for preventingautomatic reset operation of said mechanism until the breaker-controlledline is opened by operation of the first mentioned means, the secondmentioned means being deenergized automatically, and rendered inoperableto prevent reset, immediately upon opening of the aforesaid line.

3. An automatic release and reset circuit protecting breaker includingautomatically operating releasing and resetting mechanism, meansoperable for opening the breaker controlled line, and means operableautomatically after, and supplied with electrical energy only by andupon, an automatic release operation of said mechanism for preventingautomatic reset operation of said mechanism until the breaker-controlledline is opened by operation of the first mentioned means, and a latchoperable manually, at any stage of the functioning of the mechanism, forpreventing automatic reset operation of said mechanism, without causing,requiring, or preventing, automatic release operation of said mechanism.

4. An automatic release and reset circuit protecting breaker includingautomatically operating releasing and resetting mechanism, meansoperable for opening the breaker controlled line,

and means operable automatically after, and supplied with electricalenergy only by and upon, an automatic release operation of saidmechanism for preventing automatic reset operation of said mechanismuntil the breaker-controlled line is opened by operation of the firstmentioned means, the second mentioned means being deenergizedautomatically, and rendered inoperable to prevent reset, immediatelyupon opening of the aforesaid line, and a latch operable manually, atany stage of the functioning of the mechanism, for preventing automaticreset operation of said mechanism, without causing, requiring, orpreventing automatic release operation of said mechanism.

5. An automatic release and reset circuit protectim; breaker comprisinga main circuit in series with the supply and load and, includingcontrolling parts for releasing or resetting the breaker, andautomatically operable means for moving said parts to released position,on a n circuit overload, and for thereafter mo said parts to resetposition, means operable for open ing the main circuit and a shuntcircuit inclu means for preventing the reset operation of the firstmentioned means so long as the circuit overload persists, the shuntcircuit :2" being completely deenergized but being nged to be suppliedwith electrical energy autotically by and upon the overload-caused opeoi the main circuit, and to be deenergized thereafter upon the openingof the main circuit by operation of the second mentioned means.

6. An automatic release and reset circuit protecting breaker comprisinga main circuit in series with the supply and load and, inclu i ltrolling parts for releasing or resetting the breed:- er, andautomatically operable means for moving said mrts to released position,on a limo; :41 cir-= cult overload, and for thereafter moving mid toreset position, means operable ior opening the main circuit and a shuntcircuit including means for preventing the reset omration oi the firstmentioned means so long as the circuit overlom persists, the shuntcircuit normally being completely deenergized but being gm to besupplied with electrical energy automatically by and upon theoverl-caused opening of th was circuit, and to be deenergized thereafterupon the opening of the 11 ct by otion oi the second mentioned baa-u theshunt circuit being deenergized automati and rendered inoperable toprevent reset operation, ediately upon opening the main circuit.

7. an autotic release and reset circuit pro= tecting br 1.5L comprisinga main circuit in se= ries with the supply and load and, inclu conpartsfor rel or reset a the brmlser, and automatically operable means formoving said parts to released position, on a cir= cult overload, and forthereafter 21101251 mid parts to reset position, means operable foromning the main circuit and a shunt circuit including in for preventingthe reset operation of the first mentioned means so long as the circuitoverload persists, the shunt circuit nally being completely deenergizedbutb t god to be supplied with electrical en auto after opening of themain ircuit by ,operatlon of the second mentioned as. and

a latch operable ually, at any stage of the functioning of the mech afor preven automatic reset operation of said .mec- 1r vrith= out iwiring, or preven, automtic operation of said 1 r. m.

Slhdn automatic and reset in :s prober comprising a circuit in serieswith the supply and load d, including controlling parts for 1 orresetting the hm)!- er, and automatically operable m tor m said to re w.w: position, on a main ct overload, and for ereatter moving small 1 toreset position, n operable-for one main circuit and a shunt circuitinclu t there=' accents 11-1.: of the m circuit by operation of thesecond mentioned means, the shunt circuit being deene ,,1;-..iautomatically and rendered inoperable to prevent reset operation,immediately upon s 1 v the main circuit, and a latch operable manually,at any stage of the functioning or the mechanism, for preventingautomatic reset operation of said mechanism, without causing, requiring,or preventing, automatic release operation of said mechanism.

9. An automatic overload release and reset circult breaker including amovable circiut closing member, means providing therefor a constanttendency towards cyclic movement to and from released reset positions, acircuit responsive control no for controlling the cyclic movement ofsaid circuit closing member in release and reset cycles, means operablefor opening the breaker controlled line, and means operating on releaseoperation of said member for thereafter preven reset operation of saidmember and rendered inoperable for preventing reset immediately uponopening the breaker controlled line by operation of the first mentionedmeans.-

lll. An automatic overload release and reset circuit breaker including amovable circuit closing mber, means providing therefor a con= stunttendency towards a cyclic movement to and from reld and reset positions,a circuit responsive control means for controlling the cyclic movementof said circuit closing member in rel and reset cycles, means operablefor opening the breaker controlled line, means operating on releaseoperation of said member for thereafter preventing reset operation ofsaid member and rendered inoperable for preventingreset immediately uponopening the breaker controlled line by operation of the first mentionedmeans, and a latch operable manually, at any stage of theiunctioning ofany of the aforesaid parts for preventing automatic reset operation ofsaid mber, without causing, requiring, or preventing auttic releaseoperation of said mecha- 11. An automatic release and reset circuitprotecting ber including automatically operating rel and resettingmechanism, means operable for opening thebreaker controlled line, and moperable ediately after, and supplied with electrical energy only by andupon a autotic rel operation of said no, for thereafter preventingautomatic reset operation of said nice 1 we said means being renderedinoperable ior preventing reset immediately upon a the b a: 1 controlledline by operation of the t tioned means.

12. An we tic release and reset circuit protesting ber includingautomatically operating releasing andresetting mechanism, means thebreaker controlled line,

, ble immediately after, and supplied with electrical energy only by andupon an but: t operation of said mec, for thereaiter preventingautomatic reset operatlon of rsa.d means being rendered inoperable forpreventing reset edia upon ope the breaker controlled line tion of thefirst mentioned means, and mi ually, at any stage or the oi any of theaforesaid parts for preyen automatic reset operation of said member,without causing, requiring, or preventautomatlc release operation ofsaid mechaawait/e claim 11 wherein the automatic reset preventing meansoperates to prevent reset before the automatic reset mechanism canoperate to cause reset.

1%. A combination of the character specified in claim 11 wherein theautomatic reset preventing means operates to prevent reset before theautomatic reset mechanism can operate to cause reset, the former beingconstructed to have an instantaneous action, and the latter being con--structed. to have a delayed action.

WIILIAIVI H. FRANK.

